Switch between multiple lists stored in scene
This is my current solution that seems to work? But I'm sure there is a much better way out there!? :)

def list_obj_append(Id):
    global curList
    obj_selected = [o for o in bpy.data.objects if o.select]

    curList = scn["set_1"]
    scn["set_1"] = curList

    for ob in obj_selected:
        curList.append(ob.name + suffix[Id])

    scn["set_1"] = curList
    curList = scn["set_1"]

    return curList